more than 11,000 people packed a high school in las vegas sunday night to listen to president obama. >> stand with me and work with me, we'll win clark county again. we'll win nevada again. we'll win this election again. >> reporter: it was the president's last scheduled appearance before the first presidential debate on wednesday. like his opponent, he's trying to lower expectations. >> i know folks in the media are speculating already on who is going to have the best zinger. governor romney is a good debater. i'm just okay. >> reporter: mitt romney heads to colorado today for his last minute cram session. romney fit in another rehearsal after church in boston on sunday. he's been practicing since june. while many believe wednesday's debate is a must-win for romney, his running mate paul ryan says this will not be a defining moment. >> i don't think one event will make-or-break this campaign. >> reporter: apparently not everyone got the memo to down play expectations. >> thursday morning you'll all be scratching your heads and say wow we have a barn burner now. >> reporter: the deba